Self-winding clock



July 28, 1953 o. SCHILD SELF-WINDING CLOCK Filed July 50, 1946 Hid 17v VF/V rm? 0 fro Jar/1.2:

Patented July 28, 1953 UNITED STATES PATENT 'OFFICE Application July 30, 1946, Serial No. 687,202

In Switzerland January 11, 1946 7 electromagnet, which is fed by a source of electrical energy, and an armature, which is adapted to oscillate between the polar member of the electromagnet, the said device being characterized by the fact that this armature carries a pawl which is adapted to actuate rotatively a ratchet wheel, which is integral with the axle of the barrel of the clockwork mechanism, so as to wind up the spring of the latter, this ratchet wheel being, in addition, in engagement with a stop pawl that is carried by an arm which is adapted for pivoting and supports a rod provided with a contact member which is adapted, on the one hand to control the passage of the electric current so as to bring about each oscillation of the above mentioned armature and, on the other hand, to control the passage of the said electric current which ensures this oscillation when the maximum and minimum tensions of the barrel spring reach a predetermined value.

The accompanying drawing shows, by way of example, an embodiment of the device forming the subject matter of the invention.

Figure 1 is a diagrammatic view in plan, and

Figure 2 is a view of a constructional detail.

The device represented comprises an electromagnet 1, between the polar members 2 and 3 of which an armature 4, which is pivoted on an axle 5 carried by the plate 6 of a clockwork mechanism, is adapted to oscillate. The armature 4 is acted upon by a restoring spring l of the action of which thereon is limited by a stop 8.

I' he armature 4 carries, in addition, step-bystep device consistin of a pawl 9 which is adapted to actuate rotatively a ratchet wheel it which is integral with the axle or shaft'li of a spring 13 carrying barrel [2.

An arm l4, one of the ends of which is provided with a stop pawl 15 and the other end of which is pivoted on an axle l5 of the plate 6, is adapted to oscillate or to be displaced between stops H and I8 under the action of the said stop paw1 15 on the one hand of a restoring spring 19 on the other; in fact, in accordance with whether the tension of the latter on the arm I4 is greater or less than the pressure exerted by a tooth of the ratchet wheel IE! on the stop pawl IS, the said arm l4 comes to bear against one or other of the stops I1 and I8.

The arm [4 also supports a rod 253 which is provided with a contact member 2! that adapted to press and rub against an insulating gtork 22 ,2 which is mounted loosely on the axle 5 of the armature 4; this fork 22 carries a plate 23 made of a well conducting materialwhich is adapted to connect electricallythe contact member- 2l with the uninsulated axle 5 and with the frame.

The armature 4 carries a stud 24 which is arranged between the teeth 25 and 26 of the fork 22 so as to drive the latter when member 4 oscillates about the axle 5; the result, of this is to make and break alternately the electrical connection between the axle 5 and the contact member 2|; in fact, the latter can rub against the fork 22 on coming successively into contact on the one hand with its insulating part and, on the other hand, with the plate 23.

The rod 20, which is insulated from the frame, is connected by an electric conductor 21 to one of the terminals of a source of electricity 28, the other terminal of which is connected in series with the electromagnet l and with the plate 6 with the aid of conductors 29 and 30.

The device represented operates as follows:

1. In order to cause the armature 4 to oscillate, the circuit of the source of electricity 28 being closed by the conductor 21, the contact member 2i, the plate 23, the axle 5, the frame, the electromagnet l and the conductor 29, the armature 4, under the action of the coil I, pivots in the direction of the arrow 3|; when it is displaced through a certain angle, its stud 24 strikes against the branch 25 of the fork 22 and drives the latter in the same direction with the result that contact betweenthe small plate 23 and the contact member 2| is broken and it follows that,

'as the electromagnet I is no longer energized,

owing to the oscillation of the armature 4, the

pawl 9, which is pressed by the spring 33, drives rotatively the ratchet wheel Ill step-by-step and, by means of the latter, the axle II, to which is fixed one of the ends of the spring l3; the result of this i to tension the latter; on each oscillation of the armature 4, during the backward movement of the pawl 9, the wheel It is stopped by the pawl l5, which is fitted to the arm [4, and is pressed by the spring 34. When the tension of the spring [3 reaches such a value that the pressure, against the pawl I of the teeth of the wheel [0 is greater than the tension of the spring I9, the arm I4 pivots about the axle l6 and comes to bear against the stop [7; the result of this pivoting of the arm I4 is that the rod 20, which is carried by arm I4, is displaced so that the contact member 2| assumes position 35 (Figure 2) and, consequently, can no longer ensure the closing operation of the circuit with current source 28; the result of this is that the oscillation of the armature 4 as well as the winding-up of the spring [3 are stopped. When the tension of the latter has, owing to the operation of the clockwork mechanism, diminished sufficiently for the tension of the spring '19 to be no longer balanced by the pressure of the teeth of the wheel [2 against the stop pawl IS the arm I4 again pivots about the axle l6 and comes to bear against the stop l8'whilst displacing the rod 20 and the contact member 2! which again comes to press against the fork 22 so as again to ensure the oscillation of the armature 4 and the winding-up of the spring [3.

The device represented therefore renders it possible, by means of a periodic winding-up, to ensure for the barrel spring 13, a tension which is continuous between a predetermined minimum value and a predetermined maximum value; this renders it possible to ensure, on the one hand, a transmission of a practically constant force to the trains of wheels of the clockwork mechanism under consideration and, on the other hand, a fixed reserve of force for the spring 13.

In addition, the plate 23 and the contact member 2I clean themselves by rubbing against each other; this ensures a good contact between these two members.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is:

1. A device for electrically performing winding operations of the spring of a clockwork mechanism having a barrel for the spring, a frame, an electromagnet, a source of electrical energy including an energization circuit for said electromagnet, and an armature adapted to oscillate between the poles of said electromagnet; comprising a first movable contact member in said energization circuit and carried by said armature, a ratchet wheel connected to said barrel of said spring, a pawl carried by said armature and adapted to actuate said ratchet wheel so as to wind up said spring, an arm arranged for pivotal movement on said frame, a stop pawl for said ratchet wheel and supported by said arm, and a second movable contact member in said energization circuit and carried by said arm and adapted to coact with said first movable contact member to thereby control the passage of electric current to said electromagnet.

2. A device according to claim 1, including an axle about which said armature of said electromagnet oscillates, and a fork of insulating material loosely mounted on said armature axle.

3. A device according to claim 1, including a spring controlling said pivoted arm, the force of said spring on said arm being directed opposed to the force of said barrel spring.

4. A device for winding-up the main spring of a clockwork mechanism comprising, an electromagnet including spaced poles, an energization circuit for said electromagnet, an armature mounted to oscillate between said poles in response to energization of said electromagnet, first contactv means in said circuit and operatively connected to said armature, pawl and ratchet means operatively connected to said armature and spring for winding up said spring in response to oscillation of said armatures, second contact means in said circuit and engaging said first contact means for periodically completing said circuit, and a holding pawl engaging said ratchet and operatively connected to said second contact means for urging the latter out of engagement with said first contact means upon winding up of said main spring to a predetermined tension.

5. A device for winding-up the main spring of a clockwork mechanism, comprising an electromagnet including spaced poles, an energization circuit for said electromagnet, an armature mounted for oscillatory movement between said poles in response to completion of said circuit,

, fork means pivoted on said armature and including a first contact in said circuit, means on said armature and engageable with said fork means for pivoting the latter, pawl and ratchet means on said armature for imparting a step by step rotation to said main spring in responseto said oscillatory movement, a second contact in said circuit and movable into abutment with said fork means, said second contact being engageable with said first contact in response to pivotal movement of said fork means for periodically completing said circuit, and resilient means operatively connected to said second contact for bracing the latter into engagement with said fork means.

6. A device according to claim 5, including a holding pawl engaging said ratchet and operatively connected to said second contact for urging the latter out of abutment with said fork means upon winding-up of said main spring to a predetermined tension.

7. A device according to claim 6, including a pivoted arm mounting said second contact for movement into and out of abutment with said fork means, and stop means for limiting the pivotal movement of said arm.

SCHIL-D, OTTO.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,837,929 Warren Dec. 22, 1931 1,993,005 Hamill Mar. 5, 1935 2,044,286 Fowler June 16, 1936 FOREIGN PATENTS Number Country Date 437,001 France Apr. 11, 1912 649,056 France Aug. 21, 1928 

